All our milage is wrong!!

[Ger Keane]

my car is fitted with an external speedo/rev counter/milage counter. this is more accurate than the speedo in the dash, i know this as the limiter kicks in at 180kmh on the external speedo while my dash clock goes well passed 180kmh. i found this out months ago but only realised the knock on effects recently. say when im actually doing 100kmh, the dash speedo says 108kmh approx. this means the stock dials are about 8% out...................stay with me.................it means the milage that is being clocked up is about 8% more than the real figure, so the dash is actually overstating the real milage of the car. so say for example your milage reads 108,000km then this is actually 8000km more than the truth!

just something interesting i thought i would share with ye!!

 

[Yakozan]

Most cars show to much speed on the speedocluster.
Don't know why really. Might be a precaution by the manufacturer so they won't get sued if someone was going to fast in real life, but not on the speedo.
I would beliave that the odo goes by the ECU speed signal which shows a different speed compared to the speedocluster.

 

[Ger Keane]

Most cars show to much speed on the speedocluster.
Don't know why really. Might be a precaution by the manufacturer so they won't get sued if someone was going to fast in real life, but not on the speedo.
I would beliave that the odo goes by the ECU speed signal which shows a different speed compared to the speedocluster.

ya thats what i thought aswell but theres a trip counter on my external speedo aswell and this showed i had done 100kilometres when the odometer said i had done 108kilometres

 

[Yakozan]

Now it's getting interesting
Well. I'm not really worried. I don't think this is just a S15 problem.
Nut why the odo doesn't go by the ECU speed signal is a mystery as that should be more accurate.

 

[Silverstreak]

This is the case with most manufacturers, with honda being one of the ones that over exagerates the speed the most, my Prelude reads about 6mph more than my sat nav recorded speed and the Silvia about 4mph. Like Yakozan said, as far as I'm aware this is to cover the manufacture's arses! But it does give you a certain margin of error to argue with over zelous plod! (Not condoning speeding here-Its for Idiots! :nod

 

[Nicely]

Fit different sized tyres and the reading will change again. Fit certain sized tyres and you'll find the reading nearly as accurate as GPS.

 

[Yakozan]

Fit different sized tyres and the reading will change again. Fit certain sized tyres and you'll find the reading nearly as accurate as GPS.

true, but then the speed in the ECU would be wrong. Don't know what the ECU uses the speed for though so might not matter.

 

[Topper]

This is common place in the car industry, its better than the speedo being out the otherway, then you would get stopped even more

 

[s15 Damo]

my car is fitted with an external speedo/rev counter/milage counter. this is more accurate than the speedo in the dash, i know this as the limiter kicks in at 180kmh on the external speedo while my dash clock goes well passed 180kmh. i found this out months ago but only realised the knock on effects recently. say when im actually doing 100kmh, the dash speedo says 108kmh approx. this means the stock dials are about 8% out...................stay with me.................it means the milage that is being clocked up is about 8% more than the real figure, so the dash is actually overstating the real milage of the car. so say for example your milage reads 108,000km then this is actually 8000km more than the truth!

just something interesting i thought i would share with ye!!

Mine is the very same , i have a little external meter like you, this speed is prob through a sensor alot closer to the wheels the other is coming from the engine-ecu, the loss is through the transmission i'd say